You arrive as a student or visitor on a 6 month visa !
Then you get married!
I visa status change from visitor to married to a USA citizen can be made through an immigration attorney in the USA!
If you get married in Thailand she can no longer ask for a visitor visa and then claim she’s married as the status is known before travel which puts you in a ambiguous situation!
It’s become really complex in the USA and I strongly suggest you get a god immigration attorney!
The one you want to seek out are the ones that retired from US immigration, as they intimately know the process and people within the system.